Tractor



1920 ,4 Sheets-Sheet 1 R. E. ROY

TRACTOR Filed May 24 July 8 E924.

1N vmx TO I\ RoberZE Roy.

R. E. ROY

TRACTOR 1920 4 Sheets-Sheet, 2

Filed May 24 R. E. ROY

TRACTOR Filed May 24, 1920 4 Sheets-Sheet 61IfIII/IIIIIIIIZIIIIIIII/I/III/IIIIIII/I/IIII/III!IIIIII/I/IIIII/lllll/IIl/IM,

v IN V EN'PO R f? ajerifl [1 19 y.

Patented July 8, i924.

tsetse ROBERT-E. ROY, O'FSANTA,ROSA, CALIFORNIA.

TRACTOR.

Application; fi1ed,May 24, 181,29. SerialNio. 383,679.

To. all whom it may concern:

Be it, known that. I, ROBE-R1: ELRoY, a

citizen of the United States, residing at.

Santa Rosa, ini the county of Soho-ma and State of California, haveinvented a new and. useful Improvement in Tractors, of which the,following is: a, specification.

This invention relates to tractors espe- I cult1vat1ng, hauling, and.for similar purposes; the obcially adapted for plowing,

ject in view being to provide; a practical tractor embodyingfa. novelarrangement of steppers which. form a traction. means, and also, a,support for; the tractor proper during operation.

The chief. fea ure of. the invention. resides in. the traction means andin the particular formation, mounting, oper tion and arrangement of. thestep ers whereby each stepper is driven rearwardlyduring its working ortraction stroke at. a predetermined speed and is returned or drivenforward to. the initial point of its. working stroke, at a relatively:accelerated speed,

vthereby compensatingfor the time that,

wonldotl'ierwise, be, lost in the elevation and:

depression of} each stepper during the com-.

plete orbit of movement, thereof.

Another object is. to provide a structure whereby each. stepper is.moved. forwardly toiIts initial point of operation andis started} uponits, working stroke before the companion stepper operating in rearthereof leaves the ground so thatthe frame is supported. at opposite,sidesby at least one step,

perall} of the time, thus causing the machine to travel, forwardly withthe frame at. uniform level and with uniform speed, and preventing anyjarring action. or vibration due to] irregular operation of thesteppers. I

Another object of the invention 1s to providea pair of dr ving membersfor each steppen further a support whereby the steps pers, are engaged,at two. points when pro.- pelled and similarly engaged at two polntswhen elevated, advanced and depressed.

Another object of. the in ention is t provide a. rigid fr me forsupporting each paid of steppers and a rigid connection between saidframe nd the main frameof the tractor.

Further objects will hereinafter appear.

The. invention. consis s. of t e, parts a theconstruotion, combinationand arrangement of par s. as rei after ore ful y departly broken away.and partly in section.

ig. 3 is;an,e1 1d'view of the tractor.

Fig, 4, is. a central vertical; cross section taken on line 44,, Fig, 1.

Fig, 5 is an, inside side elevation, ofoneof the steppers, partly brokenaway.

Fig. 6 is a detail section] taken on line 6, 6',;Fig. 5.

Referring to the drawingsin detail A. in di'cates the main. frame of thetractor, including longitudinal and transverseframe members as shown atQand 3, said frame being supported by a plurality of sets of steppers,such as indicated at 4; 5', 6 and 7, each of which is provided withtread members. 8 of suitable formation as will hereinafter be describedlV 1 As illustrated in the drawing two sets of'steppers are employed andthere are two st'eppers in each set, one set being located at each side.of the longitudinal axis of the machine. The steppers operatealternately or one'a fter the other so that while one stepper is beingdriven rearwardly to.

drive the machine ahead, the companion stepper is being carried"forwardly at a relatively accelerated speed to take the place of theworking stepper when the latter 3P7. proachesthe rearward limit of itsmovement and moves upwardly out of contact with the surface of theground.

Each stepper is provided with a pair of rack members 9 and 10, said rackmembers being disposed on. different planes. one above the other andinterspaced with relation to each other. These rack members are secured.to. a side plate 11 andare interspaced' by means of guide tracks 12';the guide tracks 12 and the racks 9 and 10 beingsecured to the plate 11by bolts 13 or any other suitable means. The steppers serve as trackmembers over which the tractor proper travels when travelling and theyare therefore alternately advanced or laid in front of the tractor to.permit continuous forward movement of the same. This is accomplished inthe following manner: Suitably supported on the main frame A is anengine of suitable construction and journalled crosswise in the frame isa shaft 14 to which power is transmitted from the engine through a wormgear drive 15; a transmission 16 of suitable construction beinginterposed between the worm drive and the engine proper to permit thespeed changes and the reverse movement to be transmitted when desired.The shaft 14f is ournalled on and supported by the main frame A.Slidably mounted but keyed to the shaft on each end thereof is a sleeve16, which terminates in a friction clutch 17, and turnably mounted oneach end of the shaft is a gear 18, which is connected with acooperating friction clutch 19. These clutches are normally held inengagement by springs 20 interposed between the worm gear housing andthe sleeves 16, but they may be manually released whenever desired byoperating levers such as shown at 21.

Supported by the main frame is a pair of cross frames 23, and hung fromthe outer ends of said frames or otherwise secured thereto area pair ofchannel frames 2e, one on each side of the main frame and runningparallel therewith. Secured on each channel frame in alignment with theshaft 14: and directly below the same is a bearing member 25, andjournalled in each bearing member is a shaft 26, on which is secured apair of driving gears 27, and a pair of accelerating return gears 28.Suitably secured, or otherwise supported at the opposite ends of therespective channel frames are bearing members 36, and iournalled thereinare shafts 37, upon which are secured a pair of idling gears 38, and apair of accelerating return gears 39. The gears 27 and 38, supportedby'the respective shafts E26 and 37, intermesh with the rack gears 9 ofthe respective steppers, while the accelerating return gears 28 and 38engage the rack bars 10 of the respective steppers. Power is transmittedto the shafts 26 in. the first place from the shaft l i and the gears 18carried thereby and either gear 18 may be disconnected by releasing theadjacent friction clutch bymeans of the connected operating lever 21.This is of importance as it permits the power to be transmitted to oneside, for instance when turning or partially turning to one side oranother.

With power transmitted to the shafts, it can readily be seen that theresp 'ctive driving gears 27 will engage their racks and will in thismanner propel the tractor in a forward direction over the steppers ortrack members. The track members are arranged .in pairs on each side andare adapted to operate alternately, for instance, the track members 1and 7 may advance in unison while the track members 5 and 6 are drivingor vice versa. It is therefore possible to transmit a continuous forwardmovement and simultaneously provide a substantial support for thetractor. This is due to the fact that the track'members are advancedwith such speed that they are already in engagement with the ground andin position to support the tractor before the opposite track membershave completed their operation. The gears 27 are held in engagement withtheir respective racks by means of rollers l0 and ll and exterior andinterior guide tracks 12 and 12 These tracks are also employed for thepurpose of securing the steppers or track members against lateralmovement with relation to the gears and respective shafts.

By referring to Figs. 1., 2 and 4, it will he been that the drivinggears are of smaller diameter than the return gears, similarly that thepitch of the teeth are proportional, the pitch being smaller on thesmaller gears and racks and larger on the return gears and racks. ,Thisis of importance as both gears revolve at constant speed. The drivinggears advance the tractor. with relation to the steppers or trackmembers and as they are of small diameter, it can be seen that the speedis relatively slow. The larger return gears are held out of engagementwith their respective rack membei 's during this movement and do notengage their racks until the driving gears travel out of engagement withthe small pitched racks. However the moment the larger gears engagetheir racks, it should be obvious that the speed transmitted will beconsiderably accelerated and that the return movement of the trackmembers will therefore take place in such a short time interval thatthey are replaced and in driving position when the opposite trackmembers are just about reaching the end of their driving operation. Theaccelerated movement only takes place when the steppers are elevated andonly during the horizontal movement of the same, the elevation of eachstepper or track member, and depression of the same, being taken care ofby the smaller pitched racks and driving gears are clearly illustratedin Fig. 5. The guide tracks maintained for the purpose of retaining thedriving and return gears in mesh with their respective racks are bothexternal and internal as shown, the ends being oblong and rounded as at50 to insure a perfect operation of the track members or steppers whenbeing raised or lowered. There are two rack members 9 and two rackmembers 10 employed on each stepper. This is of course due to the factthat two idling gears, one driving gear and one return gear, areemployed in each instance. This is of importance as it first of allforms two driving connections between each track member and the tractorproper, secondly, two points of engagement when a track member is beingraised or lowered, third, it insures a positive and uniform movement ofeach track member whether returning, driving or otherwise, and fourth,

i p rmi h cen truction ofv t ack. m m

her of considerable length and;theprovision of tread plates therefor,such as shown at 60-. The tread plates, two. in. lumber, are pivotallyattached to. each Stepper 18.. all 61 llear their outer emlsand' theirinner ends are slotted as at 62 and connected by apin 63. These pins areengaged by a yoke 64 (see Figs. and 61) and as this passes upwardlybetween the rack members, and is guided between the same, it is obviousthat a resilient support may be formed by introducing springs such asshown at 65, and that pivotally and flexibly mounted tread plates are inthis manner provided which materially increase-s the traction efficiencyof the machine.

From the foregoing it can be seen that a comparatively simple efficienttractor has been provided which employs steppers or track layerspresenting a large supporting and traction surface, said track layersbeing alternately elevated and advanced to permit the tractor proper totravel over the same. The advance movement of the track layers isaccelerated and a pair of track member are therefore always in positionfor the reception and support of the tractor proper before the oppositepair have completed their rearward travel. A continuous forward movementis in this manner obtained and the speed of said forward movement may ofcourse be varied by variation in engine speed, or by shifting the gearsin the transmission 16.

Having thus described my invention, what I claim and desire to secure byLetters Patent is 1. In a tractor a main frame, a pair of steppersarranged on each side of the frame, a driving shaft extending crosswiseof the frame, two pairs of gears on each end of the shaft, one gear ofeach pair being of larger diameter'than the adjacent gear, a pair ofrack members on each stepper, one rack engageable with the small gear ofeach pair, and one engageable with the lar e gear of each pair, saidrack members being mutilated and one being arranged above the other.

2. In a tractor a main frame, a pair of steppers arranged on each sideof the frame, a driving shaft extending crosswise of the frame, twopairs of gears on each end of the shaft, one gear of each pair being oflarger diameter than the adjacent gear, a pair of rack members on eachstepper, one rack engageable with the small gear of each pair, and oneengageable with the large gear of each pair, said rack members beingmutilated and interspaced, and one forming a continuation of the other,and means for maintaining the gears in mesh with their re spective rackmembers when engaging the same.

3,. In a;tractor of the, character described a. plurality of steppers,,amain frame supported thereby, driving means on the; frame adapted, to.advance the. frame with relation to the: steppers and the, steppers wition to. the frame, pair of aligned shoes pivotally attached t'o,.eachstepperat their outer ends, and similarly connected at their adjacentends, and a. yielding support for said adjacent, ends.

4. In a. tractor of the character described a plurality of steppers, apair of aligned tread members for each stepper, said tread members beingpivotally attached at opposite ends to said steppers, a connectionbetween the abutting ends of each of said tread members and yieldingsupports for said ends.

5. A tractor embodying in combination a frame, two sets of stepperssupporting said frame and arranged at opposite sides of the central foreand aft axis thereof, an engine on said frame, driving connections between said engine and steppers, operating to drive a stepper of each setrearwardly at a certain speed and forwardly at a relatively acceleratedspeed, said driving connections including two sets of rack members oneach stepper, and two driving spur gears of different sizes meshingtherewith.

6. A tractor embodying in combination a frame, two sets of stepperssupporting said frame and arranged at opposite sides of the central foreand aft axis thereof, an engine on said frame, driving connectionsbetween said engine and steppers operating to drive a stepper of eachset rearwardly at a certain speed and forwardly at a relativelyaccelerated speed, said driving connections including two sets of rackmembers on each stepper and two driving spur gears of different sizesmeshing therewith, the major portions of said rack members being inspaced parallel relation to each other.

7. In a tractor a main frame, a plurality of steppers supporting thesame, a pair of racks at each end of each stepper, a driving gear and areturn gear alternately engageable with one pair of racks and a pair ofidling gears alternately engageable with the other set of racks.

8. In a tractor of the character described a main frame, a pair ofauxiliary frame members, one on each side of the main frame, a pair ofcross frames, one at each end of the main frame and secured thereto,means securing the auxiliary frame members to the cross frames, a pairof steppers arranged one on each side of each auxiliary frame, a maindriving shaft extending crosswise of the main frame, a gear 011 each endthereof, a driven shaft journalled on each auxiliary frame, a gear oneach driven shaft intermeshing with the gears on the main driving shaft,means carried by each th reladriven shaft adapted to advance the tractoronthe steppers, and also adaptedto elevate and advance the steppers withrelation to the tractor at an accelerated speed, said driving meansengaging one end of each stepper only, and guide means carried by theauxiliary frames and engaging the front end of each stepper only.

9. In a tractor of the character described a stepper comprising a sideplate, upper and lower rack members secured thereto, shoes carried bythe said plate, a driving shaft and a pair of gears on said shaft, oneof said gears being smaller in diameter than the other and engaging thelower rack only, and 15 the other gear engaging the upper rack only.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing Witnesses.

ROBERT E. ROY.

Witnesses:

D. R. GALE, THORN P. GALE.

